1. Field of the Invention
The invention concerns a wind power installation comprising a machine carrier which is to be fixed to the top of a pylon and which on the one hand holds the static part of an electrical generator and on the other hand supports the rotating part thereof as well as a hub of a rotor which carries rotor blades, wherein the rotor hub and the rotating part of the generator are fixed to a common hollow shaft which is supported by means of a single bearing which also carries moments on an axis tube member which is mounted to the machine carrier.
2. Description of the Related Art
DD 261 395 A1 discloses a wind power installation in which both the axis tube member and also the hollow shaft comprises two cylindrical portions which are spaced in the axial direction and which are of greatly different diameters and which are respectively connected together by a conical portion. Both cylindrical parts of the axis tube member and the hollow shaft are connected together by a respective rolling bearing, more specifically the cylindrical portion of larger diameter by an inclined roller bearing near the machine carrier and the cylindrical portion of smaller diameter at a considerable spacing therefrom on the other side of the fixing/mounting of the rotor blades on the rotor hub.
A bearing arrangement with a single bearing is known from DE 44 02 184 A1. In that case a single groove-type ball bearing is arranged at the common centre of mass of the rotatable part of the generator and of the rotor. That arrangement admittedly provides that the single bearing does not have to carry any moments and can therefore run with a comparatively low level of wear, but that arrangement suffers from the disadvantage that air gap guidance and control in the generator is not exact and therefore a larger air gap has to be set. That reduces the level of efficiency of the generator.